Gordon Christy: veterinarian and Gala, a Doberman, in New Mexico, by Barbara
Moore

Grace Chu, an American-educated Chinese forensic accountant, and John Knox, an American Iraqi war veteran, with an import/export business, working together as freelance undercover operatives around the world in the Risk Agent series by Ridley Pearson

John Comaday: police commissioner, and Larry Cohen, Manhattan Assistant District Attorney, in New York City, by E.V. Cunningham

Thud Compton: police sergeant,
later chief, and Kevin Kearnes, chief of
police of the fictional coastal town of Cutter Point, Oregon, near the
California border, and later an agent with Homeland Security in Portland,
Oregon, by Kenneth R.
Lewis

Mario Conde: police inspector in Havana, Cuba, in the Havana Quartet
and others, by Leonardo Padura

Bart Condor: tough private investigator in New York City, by Wade Wright

Timothy Cone: Wall Street financial detective in New York City, by Lawrence
Sanders

Harper Connelly: lightning survivor who can find bodies, and her stepbrother Tolliver, in Sarne, Arkansas, by Charlaine Harris

Kate Connolly: office manager, private investigator, and new mother,
in San Francisco, California, in the Maternal Instincts series by Diana
Orgain

Pauline Cook: widowed socialite and world traveller, in Chicago, Illinois,
in the High Society series, by Catherine O’Connell

Sunny Coolidge: former New York City newspaper reporter returning with her cat Shadow to Kittery Harbor, Maine, in the Sunny & Shadow mysteries by Claire Donally (Bill McCay)

Abby Cooper: “Psychic Eye” in Royal Oak, a suburb of Detroit, Michigan, later Austin, Texas, by Victoria Laurie

Alex Cooper: Assistant District Attorney in New York City, by Linda
Fairstein

Ben Cooper: detective constable
trying to fill his police sergeant father’s shoes, and new partner,
Diane Fry, recently transferred to Edendale’s force, in the Peak
District in England, by Stephen Booth